Envelope



Aug. 18, 1936.

ENVELOPE Filed Jan. 23, 1934 V. E. HEYWOOD 2 Sheets-Sheet 1 A 1936. v. E. HEYWOOD 2,051,711

ENVELOPE Filed Jan. 23, 1934 2 Sheets-Sheet 2 Patented Aug. 18, 1935 UNITED STATES PATENT OFFICE ENVELOPE Application January 23, 1934, Serial No. 707,943

5 Claims.

The present invention relates to envelopes, particularly of the type that are employed for the packaging of loose material such as seeds, or valuable articles such as coins or securities; envelopes of this type being usually characterized by double or safety folding of the walls thereof to prevent escape or removal of the contents after being sealed.

Such safety fold envelopes, as previously constructed, frequently fail of their purpose, owing to the fact that when a seal flap, coated with ordinary water soluble gum, is moistened and pressed down for sealing, the bulkiness of the contents of the envelope is liable to partially or wholly open the seal flap before the moistened gum has a chance to dry and set. Such defective adhesion of the seal flap, of course, renders ineffective the safety folding of the envelope.

According to the present invention, there is provided an envelope of the safety fold type that is adapted to be effectively sealed by the application of pressure alone to its seal flap, without moistening, the dry-sealing adhesive of the seal flap and the engaged area of the envelope body being of such a character that complete adhesion is immediately obtained upon folding over and pressing down the seal flap, irrespective of the bulkiness of the contents of the envelope. Furthermore, the adhesive is of such a character that the envelope cannot be opened without detection. The above and other advantageous features of the invention will hereinafter more fully appear from the following description with reference to the accompanying drawings, in which:--

Fig. l is a plan view of a blank for an envelope embodying the invention.

Fig. 2 is a rear view of an envelope made from the blank of Fig. 1.

Fig. 3 is a longitudinal sectional view along the line 3, 3 of Fig. 2, showing the envelope filled with bulky material, and with the seal flap closed.

Fig. 4 is a plan view of a blank for another form of envelope embodying the invention.

Fig. 5 is a plan view of the opposite side of the blank of Fig. 4.

Fig. 6 shows the blank of Fig. 4 partially folded.

Fig. 7 shows an envelope made from the blank ofFig. 4 with its seal flap open.

Like reference characters refer to like parts in the difierent figures.

Referring first to Fig. 1, which represents the blank from which the envelope is to be made, I designates the body portion or front wall of the envelope, 2,2 the side flaps, 3 the bottom flap and 4 the seal flap. In forming an envelope from the blank of Fig. 1, the side flaps 2 and bottom flap 3 are folded along the dot and dash lines 2a and 3a respectively, with the usual gumming applied to the overlapping portions of the flaps 2 and 3. The envelope then appears as shown in Fig. 2, from which it is apparent that folding of the bottom flap 3 along the line 311 also results in folding over the lower marginal portions of the side flaps 2, 2 so that the bottom of the envelope is effectively sealed against the escape of loose material therein, due to the double or safety folding of both its front and rear walls.

In closing the envelope of Fig. 2, after being loaded, the seal flap 4 is normally folded along the line M of Fig. l, which folding results in also folding down upper marginal portions of the side flaps 2 to provide double or safety folding similar to that provided at the bottom of the envelope. However, as previously pointed out, when an envelope of this type is loaded with bulky or loose material, dimculties have been encountered in f astening down the seal flap i with the ordinary water soluble gum, so that the seal flap tends to separate from the rear wall of the envelope before it is dried, thereby nullifying the effect of the safety folding.

According to the present invention, complete adhesion of the seal flap 4 to the body of the loaded envelope is assured by coating the seal flap, at 5, and a somewhat larger area of the rear wall, at 6, with an adhesive or gumming of such a character that any portion of the gumming 5 or 6 will adhere to another portion of the gumming upon dry contact, while no portion of the gumming will adhere of itself to an ungummed surface. Obviously, the gumming 5 or 6 may be applied either to the blank of Fig. l, or to the envelope of Fig. 2, as desired, and a narrow ungummed zone I is left between the gumming 5 and 6 so that the adhesive will not film over and tend to close the mouth of the envelope. Preferably, the gumming is in the form of a dispersed rubber solution, or natural or compounded latex, the invention also contemplating the use of other similar dry-sealing adhesives in the form of thermo-plastics such as arclor resins or galyptols, either alone or in combination with rubber.

When the seal flap 4 is folded over as shown in Fig. 3, to bring the gumming 5 into engagement with the gumming 6 and pressure applied to the overlying gummed surfaces, complete adhesion between the gummed surfaces immediately results. Owing to the very close adhesion that is obtained by use of the latex base gumming, the flap 4 is uniformly adhered to the rear wall of the envelope over the entire area of the gumming 6, even though the envelope be loaded. with bulky material, as indicated in Fig. 3. when utilizing quick sealing envelopes embodying my.

invention in connection with loading or filling machinery, it is possible to dispense with the means heretofore employed for holding the moistened seal flaps closed until the gum has stuck.

thereby greatly simplifying the construction and operation of such machinery.

Referring now to Figs. 4 to 7 inclusive, there is shown a modified form of envelope particularly adapted'for use by banks or brokerage houses for the transmission and storage of securities and other valuable papers or currency. Such an envelope, when once made up and sealed, cannot be either inadvertently or purposely opened for the removal of the contents without detection, since such opening will practically destroy the envelope, as will hereinafter appear.

In Fig. 4, a blank for forming the security envelope is shown as consisting of a body or front wall 8, with side flaps 9, 9, a bottom flap I II and a seal flap H. In forming an envelope from the blank of Fig. 4, the side flaps 9 are first folded over into overlying relation along the dot and dash lines 9a, see Fig. 6, then the bottomilap I0 along the line Illa, and finally the seal flap H along the line I la. As is evident from a consideration of Fig.7, folding along the lines Illa and Ila results in folding over both the upper and lower marginal portions of the side flaps 9; consequently, the envelope provides safety folds along both its top and bottom, with no possibility of anything escaping at the four corners thereof.

In order to provide for the permanent sealing of the envelope with its contents, the invention contemplates the application of gumming to the blank of Fig. 4 in such a manner that the blank can either be converted into an envelope surrounding the object which it is desired to enclose and then sealed, in a substantially continuous folding operation, or the blank can be first converted into an envelope in the usual manner and not sealed until after it has been loaded. As indicated in Fig. 5, gumming is applied to the side flaps 9 on the reverse side of the blank, as indicated at l2 and l2a, while other gumming is applied to the bottom and seal flaps l0 and H on the front side of the blank, as indicated at l3 and M respectively in Fig. 4. In addition, the reverse side of the bottom flap I0 is also gummed at l5, as shown in Fig. 5, all of the gumming i2, I3,-l4 and I5 being of the same dry-sealing character as the gumming 5 and 6 previously described with reference to Fig. 1.

When it is desired to permanently enclose and seal an article, such as a valuable paper or currency, at the time of folding the blank, the article is placed in contact with the body 8 and the flaps 9, I0 and II folded over in the order named along the fold lines 9a, Illa and Ila, as shown in Fig. 7. This results in first contacting the gumming I2a on opposite sides of the fold line Illa to seal the bottom and then the gumming I3 with portions of the gumming i2 on the folded over side flaps 9 to seal the rear wall of the envelope. Subsequent contact of the seal flap gumming M with the combined gumming l2 and I5 shown in Fig. 7 then serves to effectively seal the flap II. In other words, with a blank formed and gummed as shown in Figs. 4 and 5, it is possible for the person responsible for the custody of valuable papers, such as bonds, currency or even coins, to enclose and seal the same with a series of substantially continuous folding operations, with the assurance that the contents canqnot be removed from the enclosure without detection. As previously pointed out, the adhesion between contacted gummed areas is'so complete 5 present invention there is provided an envelope of the safety fold type that is adapted to be 'ef- 15 fectively and permanently sealed by the application of pressure alone to itsseal flap,. without moistening, complete adhesion being obtained between the seal flap and the engaged rear wall of the envelope, irrespective of the bulkiness of 20 the contents of the loaded envelope. Envelopes embodying the invention are particularly adapted for the packaging of loose or pulverulent material owing to the certainty of the safety folding at the corners of the seal flaps so that the material cannot leak out. Dry sealing envelopes embodying the invention are also extremely useful as sputum cups in hospitals, sick rooms or elsewhere, owing to the readiness with which they may be completely sealed to prevent the escape of contents of an infectious nature.

I claim:

1. An envelope for containing bulky material having front and rear walls both extending beyond a final line of fold forming one edge boundary of the envelope when closed, a seal flap extending from the front wall beyond the edge of the rear wall, with folding over of both the seal flap and a portion of the rear wall along said line of fold serving to provide for double sealing of the envelope at its corners, and adhesive of a character adapted to adhere to itself upon dry contact applied to corresponding areas of said rear wall and of said seal flap on opposite sides of said line of fold for immediate sealing of the envelope when loaded.

2. An envelope for containing bulky material having front and rear walls both extending beyond a final line of fold forming one edge boundary of the envelope when closed, a seal fiap extending from the front wall beyond the edge of the rear wall, with folding over of both the seal flap and a portion of the rear wall along said line of fold serving to provide for double sealing of the envelope at its corners, and adhesive of a character adapted to adhere to itself upon dry contact applied to corresponding areas of said rear wall and of said seal flap on opposite sides of said line of fold for effecting an immediate closure of said envelope by pressure applied to overlying portions of said seal flap and rear wall, irrespective of the bulkiness of the contents of the loaded envelope.

3. An envelope for containing bulky material of a pulverulent nature, comprising a body permanently sealed at one end while the envelope is in fiat condition, with the other open end of the envelope body providing front and rear walls exand a portion of the rear wall along said fold line serving to provide for double sealing of the envelope at its corners, and adhesive of a char- 7 acter adapted to adhere to itself upon non-moistened contact applied to corresponding areas of said rear wall and seal flap on opposite sides of said fold line, for effecting an immediate closure of the open end of said envelope by pressure applied to the overlying adhesive areas of said seal flap and rear wall, irrespective of the bnlkiness of the contents of the loaded envelope.

4. An envelope comprising a body closed at one end and having its opposite end open, with the front and rear walls of the body extending beyond a final line of fold forming one edge boundary of the envelope, when closed, and with the front wall of said envelope extended beyond the rear wall to provide a seal flap corresponding areas of said seal flap and of said rear wall, on

opposite sides of said line of fold being provided with adhesive of a character adapted to adhere to itself upon dry contact.

5. An envelope comprising a body closed at one end and having its opposite end open, with the front and rear walls of the body extending beyond a line of fold forming one edge boundary of the envelope, when closed, corresponding areas of said front and rear walls being provided on opposite sides of said line of fold with adhesive of a character adapted to adhere to itself upon dry contact, whereby the folded over portions of both walls will adhere to the rear wall upon the application of pressure to the overlying wall portions.

VINCENT E. HEYWOOD. 

